Python for Data Analysis: Step-By-Step with Projects - Mapping New Values

The video tutorial explains how to use the map method in pandas to transform data in a DataFrame. It covers mapping values using dictionaries and functions, including built-in, lambda, and custom functions. Examples demonstrate transforming categorical data and simplifying data representation, such as converting wind directions to cardinal points.

What is the primary purpose of the map method in pandas?

• To merge two DataFrames

• To substitute values in a series

• To filter rows based on a condition

• To sort values in a DataFrame

Which of the following is a common way to map values in a pandas series?

• Using a tuple

• Using a set

• Using a dictionary

• Using a list

In the example provided, what are the values 'Monday' to 'Friday' mapped to?

• Weekday

• Workday

• Weekend

• Holiday

Which built-in function is used to count the number of characters in a string?

• count

• int

• str

• len

What is the result of applying the 'int' function using the map method on a series of floating numbers?

• A series of floats

• A series of strings

• A series of integers

• A series of booleans

What is a lambda function in Python?

• A named function

• A function that returns a list

• A small anonymous function

• A function with multiple arguments

Why might you choose a lambda function over a regular function for mapping?

• Lambda functions require less code for simple logic

• Lambda functions are easier to debug

• Lambda functions can handle more complex logic

• Lambda functions are faster

In the advanced example, what is the purpose of the regular function used with the map method?

• To calculate the average wind direction

• To filter out invalid wind direction values

• To sort wind direction values

• To simplify wind direction values to four categories

Which of the following is NOT a category used in the wind direction mapping example?

• Westward

• East

• South

• North

What is the advantage of using a regular function over a lambda function for more complex mapping logic?

• Regular functions can handle more arguments

• Regular functions are faster

• Regular functions are easier to write

• Regular functions are more readable